Mechanical Design and Theoretical Analysis of a Skip-Cycle Mechanism for an Internal Combustion Engine

Skip cycle is a working strategy for spark ignition engines, which allows changing the effective stroke of an engine through skipping some of the four stroke cycles. This study proposes a new mechanism to achieve the desired skip-cycle strategy for internal combustion engines. The air and fuel leakage, which occurs through the gas exchange, negatively affects the efficiency of the engine at high speeds and loads. An absolute sealing is assured by direct use of poppet valves, which are kept in fully closed position during the skipped mode. All the components of the mechanism were designed according to the real dimensions of the Anadolu Motor's gasoline engine and modeled in 3D by means of CAD software. As the mechanism operates in two modes, two dynamically equivalent models are established to obtain the force and strength analysis for critical components.

Authors:

• Ismail Gerzeli
• Cemal Baykara
• Osman Akin Kutlar

Keywords:

• Dynamic Model
• Mechanical Design
• Skip Cycle System (SCS)
• Valve Disabling Mechanism

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